Bridge lamp



Oct. 11, 1932. w, CASSIDY 1,882,,499

BRIDGE LAMP Filed Fe 9, 1952 2 Sheets-Sheet '1 r -I S7 Q,

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l. Y R I v v BY ATTORNEY Oct. 11, 1932. w, CASSIDY 1,882,409

BR I DGE LAMP Filed Feb. 9, 1932 2 Sheets-Sheet 2 INVENTOR -%TI'ORNEY Patented Oct. 11, 1932 UNITED STATE GEORGE W. CASSIDY, 01' FLUSHING, NEW YORK BRIDGE LAMP Application filed February 9, 1932. Serial No. 591,780.

My invention relates to lamps such as are described in my copending application Serial No. 591,778, in which I describe an indirect and direct lighting fixture. In many cases .5 the direct type of lighting is preferred for local illumination or for use in reading, whlle for general illumination the total indirect type is much more desirable. Inasmuch as this latter type requires many more lumens to be emitted by the light source to furnish equivalent lighting, it follows that attempts to combine in one lighting fixture the two types has not been successful owing to the fact that either the light was insufiicient when used as an indirect or else it was extremely wasteful when used as direct.

My invention has for its object to produce a bridge lamp which will be economical when used as a reading lamp with direct light and 29 eflicient when used as an indirect light.

A further object is to provide two light sources of different size so arranged that the larger one will be turned off when the lamp is used for reading but will be automatically turned on when the lamp is used for indirect lighting.

A further object is to provide means for turning one lamp on or off as desired to furnish the most satisfactory illumination.

A further object is to provide a construction which will provide ample ventilation for the electric lamps.

A further object is to provide a construction which will minimize if not entirely eliminate shadows.

A further object is to provide a supplemental refiector for the larger lamp so that even if the lamp shade is translucent still, when inverted for the indirect type of lighting, the lamp will be efiicient.

My means of accomplishing the foregoing objects may be more readily understood by having reference to the accompanying draw- F ings, which are hereunto annexed and made a part of this specification, in which Fig. 1 is a side elevation of my improved bridge lamp Fig. 2 is an enlarged side view partly in section, only a portion of the standard or rod being shown;

Fig. 3 is a plan of the frame work mounted inside of the shade holder; and

Fig. 4 is a detail view of the supplemental reflector. Similar reference numerals refer to similar parts throughout the entire description.

As shown in the drawings, the lamp comprises a standard formed of a rod or tube 1, to which is secured an arm 2, which is slidably secured to the tube 1 in any of the well known ways, the arm 2 is swivelled to the slide 3. I have found in practice if the arm 2 is turned upon its axis through a complete circle, the wire becomes twisted, the insulation becomes worn or unravelled in ashort time making possible a short circuit with the accompanyingdanger and damage. -I avoid this by placing two concealed. pins 4: and 5 within a' groove 6, the end of which acts as a stop in one direction while the pin 4 serves to prevent the arm being rotated too far. The arrows in Fig. 5 showing the arm in the start and stop position. It is obvious this construction eliminates any danger of the wire being twisted or chafed. At the extremity 8 of the arm 2 I mount a shade holder 9 to which may be secured a standard lamp shade 10 which may be either translucent or opaque as preferred. The vertical wall 11 of the holder 9 is provided with a. plurality of slots 12 to facilitate the escape of the heated air. A hickey 13 of standard construction serves to lock the holder 9 upon the end 8 of the arm 2, a lock washer 14 being provided to hold it securely in place. This hickey is provided with internal threads adapted to receive a bushing 15 which secures the socket supporting plate 16 in place. This plate is provided with a large number of perforations 17 which cooperate with the slots 12 to ensure adequate ventilation. Standard electric lamp sockets 18 and 19 are secured to the supporting plate 16. It is highly im portant that the centers for these sockets be located off the center of the plate 16 as clearly seen in the drawings by so locating them any standard shade frame can be used onthe lamp thus making it possible as well as con venient for the user to change the shades whenever desired. Standard shade holders are usually provided with three prongs 30, 31, 32, secured to a central disc having a central aperture through which passes a threaded pin 33 so that by unscrewing the thumb nut 34 the lamp shade and frame can be readily changed. In the socket 18 I mount a lamp 20 of say watts, while in socket 19 I mount a 150 watt lamp, the latter to be used for the indirect light. The lamp 20 is provided with a. pull switch, but I discovered in practice that if the usual flexible chain pull were employed when the lamp was inverted there was a liability of the chain becoming tangled so that when returned to the reading position it was considerable trouble to gain access to it. I avoid thisby providing a stiff beaded pull 22 which, when the lamp is inverted assumes the position shown in dotted lines Fig. 2 and when the lamp returned to "the reading position it is in place for convenient use. The lamp 21 may be provided with a standard switch 23 to turn it on when the shade has been rotated to the position shown in Fig. 2 in dotted lines. But I prefer to employ an automatic switch 24 which consists of a container 25 which is carried by the supporting plate 16. This container is made of suitable heat resisting insulating material and contains a quantity of mercury which operates to close a contact between electric conductors which carry current to the lamp 21. When this type of switch is used it is automatic and one has only to rotate the arm 2 on its aXis and when the shade turns above the horizontal the lamp 21 will be illuminated. If the lamp shade 10 is translucent it is necessary to provide a reflector for the lamp 21 when used for indirect lighting. This may be done by use of the well known Silvray lamp or it may be found desirable to supply a supplemental reflector 25, the inner surface of which is highly polished to effectively utilize all the light coming from the source 21. The reflector 25 may be secured upon the lamp 21 by a wire 26 coiled in a helix, the upper part 27 of which is fastened to an annular member of heat resisting material 28 which is fitted to the threads 29 formed on the standard socket. By locating the filaments of the lamps 20 and 21 on different planes I avoid all obj ectionable shadows. Obviously if the shade 10 is opaque and provided with a polished reflecting surface there is no necessity for a reflector for the lamp 21. Although I have described the lamps 20 and 21 being provided with separate switches it is clear that they may be arranged so that they both will remain on when desired.

Having described my invention what I regard as new and desire to secure by Letters Patent is:

1. In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions,

said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, a shade supported by the holder, two electric lamp sockets secured to the holder within the shade, switches for said sockets, electric lamps of different powers in said sockets, and a supplemental reflector for the higher powered lamp.

2. In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, an opaque shade supported by the holder, two electric lamp sockets secured to the holder within the shade, switches for said sockets, electric lamps of different powers in said sockets, and a detachable supplemental reflector for the higher powered lamp.

3. In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, a shade supported by the'holder, two electric lamp sockets secured to the holder within the shade, switches for said sockets, one of which is automatically operable on the reversal of said shade, electric lamps of diiferent powers in said sockets, anda supplemental reflector for the higher powered lamp.

l. In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, a shade supported by the holder, two electric lamp sockets secured to the holder within the shade, a stiif pull switch for one socket and a switch for the other which is automatically operable on the reversal of said shade, electric lamps of different power in said sockets and a supplemental reflector for the higher powered lamp.

5. In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions,

said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, there being ventilating slots in said holder, a shade supported by the holder, two electric lamp sockets secured to the holder within the shade, switches for said sockets, electric lamps of different powers in said socket, and a supplemental reflector for the higher powered lamp. 7

6. Ina bridge lamp having a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, a shade supported by the holder, and two electric lamp sockets secured to the holder within the shade, said sockets being located ofl' the center line of said holder, switches for said sockets, electric lamps of different powers in said sockets, and a supplemental reflector for the high er powered lamp.

7 In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, a shade supported by the holder, two electric lamp sockets secured to the holder within the shade, switches for said sockets, electric lamps of different powers in said sockets, the filaments of said lamps being on different planes.

8. In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, means to prevent a complete rotation of said arm, said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, a shade supported by the holder, two electric lamp sockets secured to the holder within the shade, switches for said sockets, electric lamps of different powers in said sockets, and a supplemental reflector for the higher powered lamp.

9. In a bridge lamp having a standard, an

arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, a shade holder carried by said arm, a shade supported by the holder, and two electric lamp sockets secured to the holder within the shade, electric lamps of different powers in said sockets, switches for said sockets, one of which is automatically operable on reversal of said shade, said automatic switch comprising a container secured to said socket support, the major portion of said container extending below said support, a quantity of mercury in said container, contacts in said container, electrical conductors which connect said higher powered lamp to said contact and a supplemental reflector for one of said lamps.

10. In a bridge lamp, a standard, an arm adapted to be rotated on its horizontal axis for direct and indirect lighting positions, said arm being slidable on the standard for vertical adjustment, a shade holder carried by said arm, a shade supported by the holder, two electric lamp sockets secured to the holder within the shade, switches for said sockets, electric lamps of different powers in said sockets, and a supplemental reflector for the higher powered lamp, there being means to ventilate said shade and holder.

GEORGE W. CASSIDY. 

